Background Color in map, Expression by Area Layer is not working.

[MuraliPrasath]

Hi,

Need help!

My expression in Map color background area layer is not working. My expression given below

 =if((aggr(sum(IB_COUNT)/sum(Total IB_COUNT),Country))<=0.81, rgb(255, 255, 204),
if((aggr(sum(IB_COUNT)/sum(Total IB_COUNT),Country))>=0.811, rgb(179, 198, 255)))